document.oncontextmenu=function(e){
        e=e||event;
        if(e.button==2 && e.target.id){
            if(e.target.attributes[0].value=="Images/w.png" && game.place.qicount<game.place.boomNum) {
                e.target.src="Images/qi.png";
                game.place.qicount++;
            }else if(e.target.attributes[0].value=="Images/qi.png") {
                e.target.src="Images/w.png";
                game.place.qicount--;
            }
        }
    game.prompt.firstChild.childNodes[1].textContent=game.place.boomNum-game.place.qicount+"帜";
    return false;
}